North St. Paul Resilient Communities Reduction in Total Phosphorus to Silver Lake Prepared by: Matthew Bonnema, Gwyneth Perry, Nathan Warner and Christopher Young Prepared for: Prof. John Gulliver and the City of North St. Paul
North St. Paul Resilient Communities Reduction in Total Phosphorus to Silver Lake
Mar 22, 2016
North St. Paul Resilient Communities Reduction in Total Phosphorus to Silver Lake. Prepared by: Matthew Bonnema, Gwyneth Perry, Nathan Warner and Christopher Young Prepared for: Prof. John Gulliver and the City of North St. Paul. Valley Branch Watershed District Silver Lake Watershed. - PowerPoint PPT Presentation
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
North St. Paul Resilient Communities Reduction in Total Phosphorus to Silver Lake
Prepared by: Matthew Bonnema, Gwyneth Perry, Nathan Warner and Christopher YoungPrepared for: Prof. John Gulliver and the City of North St. Paul
Valley Branch Watershed DistrictSilver Lake Watershed
Provided by N. St Paul
Current Stormwater Control Measure (SCM)Bio-infiltration Basin
Photograph by Nathan Warner
Current TP Loading
Bucheck, et al. 2013
● 40 ug/L 4.57 lb/year
Initial P8 Model● Precipitation File● Particle File (National Urban Runoff Program
(NURP))● Subwatershed Data
Initial P8 ModelBio-infiltration Basin Parameters
Additional Rain GardensMethods
Bio-retention Cell -3’ Mixed Media, 40% voids-14.4” ponding depth (B soils)
Minnesota Stormwater Manual
Additional Rain GardensMethods
Image: City of N. St Paul, GIS work: Nathan Warner
Placement:-R.O.W.-Soils/Infiltration-Groundwater -Road Grading-Drainage Area-Current Land Use-Curb Cuts
Additional Rain GardensResults
Bio-retention (Rain Gardens)
(Weiss, et al., 2007)
$ = 152 x (WQV)^0.776
WQV = water quality volume ~
volume infiltrated in
m^3
Adjustment for 2014 Cost
(CPI, Bureau of Labor and Statistics)
2007 Cost ($) x 1.14 “Unit” WQV = 503 cf
30’ x 7’
Additional Street SweepingMethods● Modeled in Dr. Baker’s spreadsheet
○ Prior Lake Study○ Tymco Model 600 regenerative air
sweeper○ Simple Inputs
● Frequency: 4 sweeps/year to 10 sweeps/year
Additional Street SweepingResults
Street Sweeping Frequency
TP removed [lb]
Cost per lb TP removed [$/lb]
Current Condition: 4 times a year
15.7 $47.81
6/year (spread from April to October)
20.7 $54.52
7/year from April to November
25.7 $58.54
10/year (from April to November)
31.4 $60.00
● SHASAM model by BARR Engineering
● Create Plot: % Removal vs. Avg Runoff○ Det % Removal for
Silver Lake● Convert TSS to TP
Additional SumpsMethods
* Based on http://revolutionarybaffle.com/store/. **Maintenance costs account for two cleanouts per year priced at $80 each.
Additional SumpsResults
*Based on Installation, Unit, and Maintenance costs for the 20 years of removal design life. **SLV-7 has pipe diameter 30”, all others are 15”.
● Efficiency comparison● Removal efficiency depends highly on flow
through sump and pipe diameter● Only considered NURP for SCM comparison
Summary
SCM (Most Efficient) TP Removed [lb/yr] Cost/lb TP removed
Standard Sump (per unit) 0.007-0.102 $6,583-39,013
SAFL Baffle (per unit) 0.013-0.196 $6,267-33,302
Rain Gardens* (per unit) 0.098-0.145Avg = 0.109
$8,008-13,739Avg =$8,197
Street Sweeping (4/year) 15.7 $47.81
*based on 1% imp.
Conclusions and Recommendations
• Recommend: Street Sweeping• Further work:
• develop more realistic particle file• more hydrologic data
Related Documents
